• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.4
• /
• pp.90-98
• /
• 2021

Since 2017, the Occupational Safety and Health Act has been fully applied to school food services, and risk assessments have been implemented since 2019. The introduction was slow compared to other industries and was evaluated by non-professional nutritionists, so there was a limit to establishing the system. All schools under the Seoul Metropolitan Office of Education apply the KRAS every year in accordance with the OSH Act for school foodservice and a notice from the Ministry of Employment and Labor. A risk assessment is applied according to legal regulations. On the other hand, the effectiveness of risk assessment has been questioned because the frequency and intensity criteria of the risk are qualitative and subjective. Based on the accident statistics of catering workers, the frequency and intensity criteria of risk were presented quantitatively and objectively, and a risk assessment was conducted by applying a new calculation standard for some work during the catering service and compared with current risk assessment results. The risk was increased, and the improved effectiveness was confirmed by the specific suggestions for improvement. Thus, the pilot evaluation for the entire food service should be expanded, and the feasibility confirmed. The pilot evaluation should be applied to all schools to enhance the effectiveness and operability of the risk assessment.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.16 no.4
• /
• pp.334-345
• /
• 2006

The objectives of this study were to analyze and compare 24 hrs personal exposure levels of MF at microenvironments such as home, school, educational institute, internet pc game room, transportation, and other places according to time activity patterns using various metrics for children attending the primary schools located near and away from the power lines, and to characterize the major microenvironments and impact factors attributed personal exposure level. The study was carried out for 44 children attending a primary school away from the lines(school A) and 125 children attending a school away from 154 kV power lines(school B), all who aged 12 years and were 6 grade, from July 2003 to December 2003. All participants filled in a questionnaire about characteristics, residence, use of electrical appliances and others. Children wore a small satchel in which EMDEX II and Lite (Enertech, Co. Ltd) and a diary of activity list for period of registration in 20 minutes blocks. All statistical calculations were made with the SAS System, Releas 6.12. The summary of results was presented below. First, about the characteristics of subjects, there no differences between two groups. The subject almost spent about 56 % of their time at home and about 20~25 % of their time at school. Fifty percent of children spent 2 hours at private educational institutes. Second, the personal exposure measurements of children in school B was statistically higher than those of children in school A by various metrics such as arithmetic mean, geometric mean, percentile(5, 25, 50, 75, 95), maximum, rate of change metric, constant field metric. The arithmetic and geometric mean magnetic fields during the time the children were at school B were 0.98 and $0.86{\mu}T$ and were about 23 times higher than those of children were at school A. In conclusion, the significant major determinants of personal exposure level is the distance from the power line to microenvironments.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.9
• /
• pp.2021-2026
• /
• 2009

Toluene, xylene and styrene are volatile organic solvents that are commonly used in mixtures in many industries. Because these solvents are metabolized and then excreted in urine, their urinary metabolites are thought to be biomarkers of occupational exposure to these solvents. Therefore, a simple, rapid, and yet reliable analytical method for determining the metabolites is required for accurate biological monitoring. In the present study, a simple and rapid HPLC-UV method was developed for the simultaneous determination of eight major metabolites of toluene, xylene and styrene: hippuric acid (HA), mandelic acid (MA), o-, m- and p-methylhippuric acids (o-, m- and p-MHAs), and o-, m- and p-cresols. A monolithic column was employed as the stationary phase and several conditions, including flow rate, composition of mobile phase and column temperature, were variables for the optimization of the chromatographic resolution. All eight metabolites were successfully resolved within 5 minutes in 10% aqueous ethanol containing 0.3% acetic acid and 1.6% $\beta$-cyclodextrin, using a flow rate gradient of 1.0 - 5.0 mL/min at 25 ${^{\circ}C}$. The performance of this method was validated by linearity, intra- and inter-day accuracy, and precision. The linearity was observed with correlation coefficients of 0.9998 for HA, 0.9999 for MA, 0.9989 for o-MHA, 0.9998 for m-MHA, 0.9991 for p-MHA, 0.9997 for o-cresol, 0.9998 for m-cresol, and 0.9986 for p-cresol. The intra- and inter-day precision of the method were less than 5.89% (CV) and the accuracy ranged from 92.95 to 106.62%. The validity was further confirmed by analysis of reference samples that were prepared by the inter-laboratory quality assurance program of the Korea Occupational Safety and Health Agency (KOSHA, Seoul, Korea). All measured concentrations of the analytes agreed with the certified values.

• Industry Promotion Research
• /
• v.8 no.4
• /
• pp.37-46
• /
• 2023

Due to the aging, advancement, and complexity of chemical facilities, non-routine work such as facility inspection, repair, or maintenance work is increasing. Of the 1,483 accidents that occurred over the past 10 years at chemical product manufacturing sites subject to PSM, accidents that occurred during non-routine work accounted for 56% (932 Cases) of the total. It can be seen that more accidents occur during non-routine work than during routine work. In particular, in order to improve the economy and efficiency of factory operation, there are cases where some facilities are stopped without stopping the entire factory and then inspection, repair, or maintenance work is performed while isolated from the operating facilities. Therefore, first, a safe isolation method must be selected by establishing an isolation standard (Baseline Isolation Standard) based on the chemicals handled, operating conditions, and risk level of the equipment in the chemical plant. Second, since current domestic laws and standards do not suggest the need for specific quarantine standards, it is necessary to institutionalize the preparation of quarantine standards. Technical and institutional improvements are needed to prevent fires, explosions, and poisoning accidents caused by leaks of chemical substances.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.24 no.4
• /
• pp.501-508
• /
• 2014

Objectives: This study identified the general characteristics of asbestos inspection/analysis laboratories in Korea and confirmed the actual situations in terms of technical aspects from these characteristics. In addition, given the background of the current problem, it offers preliminary data for determining future plans for improvement. Methods: A questionnaire was developed and distributed to the asbestos inspection/analysis laboratories that used the ISO/IEC 17025 for asbestos sampling and testing by UKAS(United Kingdom Accreditation Service) and the Korea Laboratory Accreditation Scheme(KOLAS). A total of 202 institutions in Korea were selected for the study and 145(71.8%) questionnaires were returned. Results: The number of personnel of the surveyed institutions averaged $4.2{\pm}2$ and 79.3% operated with less than five persons. In terms of education, the capital and other densely populated areas showed a high level of education(p<0.05). The level of education and facilities were determined by the magnitude of the institution(p<0.05). Institutions managed by highly educated directors were well-stocked with education and facilities(p<0.05). Institutions which had directors with considerable experiences received high scores overall and in particular higher scores in terms of education and facilities(p<0.05). At the level of the bottom five percent, the factor of education was 40.4% while the factor of measurement 49%, the factor of analysis 59%, the factor of facilities 61%, and the factor of survey 81%, respectively. Conclusions: To improve the quality of the institutions, in the short term, the problems identified in this study can be used to revise the related regulations. In the long term, a grading system of survey institutions needs to be established through the introduction of an accreditation system. However, the ongoing support of a government agency is required, including holding seminars and open education, suggesting guidelines for operation of asbestos inspection/analysis labs, and other means.

• Fire Science and Engineering
• /
• v.33 no.4
• /
• pp.140-151
• /
• 2019

It is to assess the indoor air quality of the chemical hazardous materials exposed to the fire after firefighters returned to the fire scene. The research subject randomly selected four fire stations located in Seoul, Korea. Two fire stations were set up as control groups after the return of the firefighting activities at the actual fire scene, and two other fire stations were set up as control groups to measure the air quality of the room at normal levels regardless of the action. We conducted 24-hour monitoring for all fire accidents that occurred in Seoul Metropolitan using fire safety map computer system. Also, indoor air quality was measured immediately after homecoming if the experiment group was to be dispatched due to an accident of intermediate or larger scale. 11 hazardous substance items such as fine dust, formaldehyde, volatile organic compounds, PAH, VCM, acidity, asbestos, CO₂, NO₂, O₃ were measured according to the process test method. Three of 11 types of harmful substances exceeded domestic and foreign standards, and one of them was found to be close to foreign standards. In particular, total volatile organic compounds, carbon dioxide and sulfuric acids were 2.5 times, 2.2 times and 1.1 times higher than the standard. Also, for formaldehyde and sulfuric acid, it was measured higher in the control group than in the case group. This findings could be used in policies to improve indoor air quality in the fire station of the Seoul Metropolitan Government.

• Journal of the Ergonomics Society of Korea
• /
• v.28 no.4
• /
• pp.1-7
• /
• 2009

The purpose of this study was to evaluate the legibility of one-syllable Korean characters with the participation of sixteen subjects. The experiment considered nine factors including age (young and old), gender (male and female), illuminance (150lx and 600lx), viewing distance (50cm and 200cm), material type (paper and LCD), typeface (Ming and Gothic), thickness (plain and bold), color contrast (black letter/white background and white letter/black background), and complexity (simple, complex, and number) to examine main effects with a $2^{6-3}\times3$ fractional factorial design. The dependent variables were minimum character size of 100% correctness, maximum character size of 0% correctness, and minimum character size of comfortable reading preference. The results of analysis of variance (ANOVA) revealed that age, illuminance, viewing distance and complexity were significant for all dependent variables, except gender which was significant only for the minimum character size of comfortable reading preference. In general, the young could see twofold smaller size letters than the elderly. The subjects could see smaller sized letters with the illuminance of 600lx and viewing distance of 50cm than 150lx and 200cm, respectively and also with numbers, simple characters, and complex characters in that order. The findings of this study could be characterized about the legibility of Korean characters and be good resources for developing its standard.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.40 no.1
• /
• pp.87-94
• /
• 2017

Many industrial accidents have occurred continuously in the manufacturing industries, construction industries, and service industries of Korea. Fatal accidents have occurred most frequently in the construction industries of Korea. Especially, the trend analysis of the accident rate and fatal accident rate is very important in order to prevent industrial accidents in the construction industries systematically. This paper considers forecasting of the accident rate and fatal accident rate with static and dynamic time series analysis methods in the construction industries. Therefore, this paper describes the optimal accident rate and fatal accident rate by minimization of the sum of square errors (SSE) among regression analysis method (RAM), exponential smoothing method (ESM), double exponential smoothing method (DESM), auto-regressive integrated moving average (ARIMA) model, proposed analytic function model (PAFM), and kalman filtering model (KFM) with existing accident data in construction industries. In this paper, microsoft foundation class (MFC) soft of Visual Studio 2008 was used to predict the accident rate and fatal accident rate. Zero Accident Program developed in this paper is defined as the predicted accident rate and fatal accident rate, the zero accident target time, and the zero accident time based on the achievement probability calculated rationally and practically. The minimum value for minimizing SSE in the construction industries was found in 0.1666 and 1.4579 in the accident rate and fatal accident rate, respectively. Accordingly, RAM and ARIMA model are ideally applied in the accident rate and fatal accident rate, respectively. Finally, the trend analysis of this paper provides decisive information in order to prevent industrial accidents in construction industries very systematically.

• Molecules and Cells
• /
• v.25 no.2
• /
• pp.272-278
• /
• 2008

The carbon-ion beam (CIB) generated by the heavy-ion medical accelerator in Chiba (HIMAC) was targeted to 7-day-old rice. Physiological parameters such as growth, and gene expression profiles were examined immediately after CIB irradiation. Dose-dependent growth suppression was seen three days post-irradiation (PI), and all the irradiated plants died by 15 days PI. Microarray (Agilent rice 22K) analysis of the plants immediately after irradiation (iai) revealed effects on gene expression at 270 Gy; 353 genes were up-regulated and 87 down-regulated. Exactly the same set of genes was affected at 90 Gy. Among the highly induced genes were genes involved in information storage and processing, cellular processes and signaling, and metabolism. RT-PCR analysis confirmed the microarray data.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.7 no.2
• /
• pp.289-297
• /
• 1997

Work-related low back pain(below LBP) is one of the major cause of morbidity, disability, limitation of activity and economic loss. Therefore the work-related LBP is one of the major issue in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the effective control programs of work-related LBP. The subjects were male workers employed at the welding and metal factory. The data was collected by self-reported questionnaire, interview and checking abdomen muscular and grasping power for two days on October, 1993. The contents of questionnaire were as follow: the experience of LBP, general characteristics, physical characteristics, employment status, type of work and working environment. The number of cases was 104 with a history of work-related LBP, so the prevalence of work-related LBP was 35.0%, and the number of controls was 140 without any history of LBP. As a result, marital status, educational level, abdomen muscular power, tenure, category of job, satisfaction of job, working posture, satisfaction for table and chair and lifting materials showed a statistical significance between the case and control groups. 284 Lifting jobs were quantified by NIOSH lifting equation method and ergonomic computer modelling methods. There were no significant differences in the action limit and disc compression force between group with LBP and without LBP. But in the lifting frequency and cumulative disc compression force there were significant differences. Therefore work-related LBP should be prevented by the ergonomic and environmental control.